A 38-year-old man from Delhi presents with a 4-month history of cough, fever, and weight loss. Chest X-ray shows bilateral upper lobe infiltrates. Sputum smear microscopy is positive for acid-fast bacilli. He was treated with standard first-line anti-TB drugs (HRZE) for 2 months but shows no clinical or radiological improvement. Gene Xpert MTB/RIF testing confirms rifampicin resistance. What is the most appropriate next step in management?

Question

Accepted Answer

A. Initiate MDR-TB regimen with fluoroquinolone, injectable agent, and bedaquiline after baseline audiometry and ECG. ## Clinical Context
This patient has **rifampicin-resistant TB (RR-TB)**, confirmed by Gene Xpert MTB/RIF. Rifampicin resistance is a marker of MDR-TB until proven otherwise, since most RR-TB cases are also isoniazid-resistant.

## Management of RR-TB / MDR-TB

**Key Point:** Rifampicin-resistant TB requires immediate switch to MDR-TB regimen. Continuing first-line drugs is futile and promotes further resistance.

**High-Yield:** The WHO-recommended MDR-TB regimen includes:
- A fluoroquinolone (levofloxacin or moxifloxacin)
- An injectable agent (amikacin, streptomycin, or capreomycin)
- Bedaquiline (Group A agent, bactericidal)
- Linezolid (if fluoroquinolone-resistant or XDR)

## Pre-Treatment Baseline Investigations

Before starting second-line drugs:

| Investigation | Reason |
|---|---|
| Audiometry | Baseline hearing assessment before aminoglycosides (ototoxicity risk) |
| ECG | QT interval assessment before fluoroquinolones and bedaquiline |
| Liver function tests | Monitor hepatotoxicity from second-line drugs |
| Renal function | Dose adjustment for aminoglycosides |
| Visual acuity (if ethambutol used) | Baseline optic nerve function |

**Clinical Pearl:** Bedaquiline is a Group A drug (most potent) for MDR-TB and significantly improves outcomes. It must be started early in the regimen.

**Mnemonic for MDR-TB regimen components:** **FIB-L** — Fluoroquinolone, Injectable, Bedaquiline, Linezolid (if needed).

## Why Surgery Is Not First-Line
Surgical resection is reserved for:
- Failure of medical therapy after 6–8 months of appropriate MDR-TB treatment
- Extensive cavitary disease with high bacterial burden
- It is NOT the initial management step.

[cite:Harrison 21e Ch 158; WHO TB Guidelines 2023]

Answer

B. Continue the same HRZE regimen for another 4 months

Answer

C. Switch to second-line drugs without drug susceptibility testing

Answer

D. Refer for surgical resection of the affected lung lobe

Explanation

Practice similar questions